The focus of our invention is on powerline communication within individual DC/DC micro-converters (also called DC Optimizer) use to convert the unregulated generated DC power from the PV into a fixed DC output voltage. This output voltage is fed into to a centralized DC/AC inverter using the power wires of the various photovoltaic strings (DC bus). One-way of making sure DC Optimizers are efficient is by adding some communication capabilities, like PLC, between the multiple DC Optimizers on the different string of the PV installation. Unfortunately, most of the communication system used today in the DC Optimizers are: a) an add-on communication system to the existing DC/DC converter making the overall solution not cost efficient; b) an energy inefficient communication solution reducing the performances of the overall PV installation. Advantages of having communication capabilities in a photovoltaic system are security, safety, remote management, etc. . . .
As a continuation of the U.S. pending patent application Ser. No. 13/227,891 entitled “Powerline Control Interface for Frequency and Amplitude Modulation Transmitter”, the focus of our invention remains at the Physical Layer in PowerLine Communications (PLC) environment.
Consequently the present invention was conceived to take advantage of the existing electronics of the MPPT function within a DC Optimizer to: a) improving the performances over a traditional Powerline Interface to transmit data on the power line by using (“pulling”) the required current from the DC Bus and therefore reducing the overall power consumption of the transmit system to only few milli-watts required by the electronics of the PV Coupler; b) eliminating the cost of the Powerline interface and therefore reducing the overall BOM of the system.
Furthermore, the use of the present invention is independent of the type of PHY modulation (ASK, FSK, S-FSK, BPSK, OFDM, etc. . . . ) and with proper adaptation of some of the electronics; the invention can be used in any frequency band. Only limitation of the created system will be to have a different communication frequency band from the Pulse Width Modulation (PWM) frequency use by the MPPT electronics. Frequency bands relevant to the smart grid market can be used, such as:                CENELEC, ARIB and FCC bands (<500 KHz),        SAE bands,        Broadband Powerline communications frequency bands        